Android 学习之--HttpClient详细使用

简介：

我们知道在Android上面，支持Socket ,HttpURLConnection（java自带的）,HttpClient(apache实现的)，这三种基本的数据通信的方式，HttpClient提供了较多的HTTP操作的实现，Android官方推荐使用。

目前，我们常用的HTTP的Method有两个POST个GET，在各种资料上面都有很很多简单的介绍。本文对其简单的介绍一个小小的补充。

官方说明：

1. Quick Start - 一个简单、完整的例子包含带参数的HTTP GET和POST。
2. HttpClient Tutorial - gives a detailed examination of the HttpClient API, which was written in close accordance with the (sometimes not very intuitive) HTTP specification/standard. A copy is also shipped with the release. A PDF version is also available
3. HttpClient Examples - 几个较为复杂的例子。
4. HttpClient Primer - explains the scope of HttpClient. Note that HttpClient is not a browser. It lacks the UI, HTML renderer and a JavaScript engine that a browser will possess.

一个SOAP的例子：

以下是 SOAP 1.2 请求和响应示例。所显示的占位符需替换为实际值。

POST /NourMSWS.asmx HTTP/1.1Host: 202.xxx.xx.xxxContent-Type: application/soap+xml; charset=utf-8Content-Length: length<?xml version="1.0" encoding="utf-8"?><soap12:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap12="http://www.w3.org/2003/05/soap-envelope">  <soap12:Body>    <GetDBtime xmlns="http://NourMS.WS.pumoto.com/">      <WSID>string</WSID>      <WSPwd>string</WSPwd>    </GetDBtime>  </soap12:Body></soap12:Envelope>

返回结果：

HTTP/1.1 200 OKContent-Type: application/soap+xml; charset=utf-8Content-Length: length<?xml version="1.0" encoding="utf-8"?><soap12:Envelope xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:soap12="http://www.w3.org/2003/05/soap-envelope">  <soap12:Body>    <GetDBtimeResponse xmlns="http://NourMS.WS.pumoto.com/">      <GetDBtimeResult>        <ResultType>boolean</ResultType>        <ResultInfo>string</ResultInfo>        <ResultDsXML>string</ResultDsXML>        <TotalNums>int</TotalNums>      </GetDBtimeResult>    </GetDBtimeResponse>  </soap12:Body></soap12:Envelope>

我们必须对HTTP的头数据添加一些数据和HTTP 协议上添加一个实体数据，如上面的实体XML。

（PS：在平常我们看到的例子中，只有UrlEncodedFormEntity,然而，请求的数据各式各样，google了都没找到，结果都是发送键值对的请求数据,最后在其HttpEntity 的子类上看见StringEntity ,）

具体的实现(代码比较猥琐)：

HttpPost httpPost=new HttpPost(url);HttpClient httpClient=new DefaultHttpClient();httpPost.addHeader("Content-Type", "application/soap+xml; charset=utf-8");//HTTP 请求是附加的头信息HttpEntity entity=new StringEntity(httpbody);//post 一段实体数据System.out.println(httpbody);httpPost.setEntity(entity);HttpResponse respons=httpClient.execute(httpPost);String content = null;if (respons.getStatusLine().getStatusCode()==HttpStatus.SC_OK) {//System.out.println();content=EntityUtils.toString(respons.getEntity());System.out.println(content);}

其中，我们看到了StringEntity 数据，文件上传可以用下面的（更多详细的例子，可以参照 http://hc.apache.org/index.html）。

InputStreamEntity reqEntity = new InputStreamEntity(
new FileInputStream(file), -1);
reqEntity.setContentType("binary/octet-stream");
reqEntity.setChunked(true);

参考：

http://hc.apache.org/index.html

.....sdk/docs/reference/org/apache/http/HttpEntity.html

....sdk/docs/reference/org/apache/http/entity/package-summary.html